Dust collector



Pateed Anais, 194s l y y nus'r COLLECTOR .i

I `Ernest n. Fisher, ram-1c, N. I." y applicati@ Nqmtere, 194i, serial 310.417,805 f invention `relates improvements in magnesium grinding and polishing booths which are Magnesiumin the formof dust or powder; be-

, 'usedin polishingan'd grinding magnesium cast- Vings or otherdust creating operations. i

ing highly explosive,my object is to provide a i booth inwhich grinding and polishing operations on magnesium castings or otherdusty operations may be carried on Without hazards due to explosion of the dust or to a dusty atmosphere arising from such operations. l

Water being one of the best agents for-wetting the dust and separating it from the air, Il employ this agent in a unique and practical manner. Exhaust fans have beenzand are `being employed for creating asuction in, such booths; but because of thehazard attendant upon the use of anymoving element to create suction or for mixing the dust laden air with water, I have eliminated all such moving parts in `my `improved grinding and polishing booth. I

In a grinding and polishing booth for hazardous dusts,` itis very essential from the standpoint y of eliminating thelexplosion hazard, that all dust` created in the grinding and` polishing operations be removed immediately and continuously from I the interior of the booth and that no part of the interior serve as a lodgementplace for the. dust.

It is also essential when such booths are used in groups of more than one booth, that such booths be not connected toa common air duct leading are a waterpipe and a water` drain.

Another object of my invention is to provide` a booth of the class described that is simple in construction y with simple non-mechanical y means in the booth itself for producing a powerful air y y through tubes to a dust collecting apparatus as an explosion in c jets in the Venturi suction necessaryto convey the dust and to wet it for separating it from the air stream.

These objects, as well as other advantagesinherent in the invention, will be apparent from a detailed description of the same in connection with the accompanying drawing in` which: Fig-l ure 1 is avertical section'of the booth taken on line I-I of Figure 3. Figure 2' is a plan view section taken on line 4-4 of Figure 3.

Referring to` Figure3 for the present, I and 2 are water and sludge collecting `tanks forming `except as justldescribed. J l 1 The `top of` tank `I is'covered with a'grille "6 copiously flooded. In the lower z claims (cl. I5`1-j2'is) with tank zfbymeans or the ai; passageway; and Venturitubes I0." Y Tank I also communicates `withtank 2 by means ofthe water passageway 5. Therefore tanks I and 2 are entirely separated Venturi tubes I0. y `Spray nozzles II located above and centered with Venturi `tubes III spray a water jet in the form of a cone under high pressure down tubes I Il and the water impingeson vaned cones I2 positioned inthe lower ends of tubes I Il. 'I'he water collects in tank 2 and drains out through conduit 4. i y

The operation of the grinding and polishing booth is as follows: Water under pressure of 20 pounds or more from manifold `I3 is supplied to nozzles II `The spray from nozzles II into Venturi tubes I0 create a powerful air suction which pulls the air through grille 6 intotank I, upward `through lair passageway 3, downward I0 into tank 2, upward through air passageway through expanding outlet I4 and spray eliminators I5.

Dust from the tions on grille 6 is pulled through the grille by the air suction created by the action of the water tubes IU. This dust comes in contact with watersprays 1 in tank I where the heavier dust is precipitated and fiowswith the water into tank 2 through conduit 5. 'I'he air with the ner dust continues upward through airgpassageway 3 contacting water spray from nozzles] `and the copiously wetted surfaces of passageway 3. Some of the fine dust is precipitated in passageway 3 and is carried backintl tank I. The air and remaining ne dust continue down the Venturi tubes and impinge with the `water on the vaned cones I2 which break up thewater into afine mist which efectually suppresses the remaining fine dust. The sloping sides S of `tank 2 tapering toward the center of the bottom of the booth.v Tank I communicates thetank cause the two streams of finely divided water and air to converge and intimately mix in the lower portion of air passageway I8 and I8 `and thence to atmosphere grinding and polishing operathus eifectually wetting the remaining fine dust and precipitating it as sludge in the bottom of tank 2 where it meets the water and sludge fromtank I and flows out through the drain I. The cleaned air continues upward through passageway Il and out to the atmosphere through eliminator plates II which separates the fine mist from the air. As nozzles 8 spray upward they assist the iiow ot air through passageway 3 into tubes I0. It is therefore clear that all surfaces with which the dust comes in contact are copiously flooded with water thus preventing the adherence o! dust which is washed to the iinal drain outlet l of tank 2. From this outlet the water and the sludge now to a sludge dewatering tank where the dust in the form of sludge is separated from the water which may be drained to a sewer or re-circulated through the spray nozzles of the booth.

Having thus described my invention I claim as new and desire to secure by Letters Patent:

1. A magnesium castings grinding and polishing booth comprising a spray chamber with grilled top serving as a grinding and polishing table, Venturi tubes adjacent to said spray chamberior exhausting air from said spray chamber, a water sprayed passageway connecting said spraychamber with said Venturi tubes, spray nozzles adapted to spray water down said tubes. impingement surfaces positioned in lower end of said tubes, a water and air receiving tank under said tubes, an air passageway communicating with said water and air receiving tank having spray eliminators arranged therein adapted to separate water mist from the air and means for draining water from said spray chamber to said water and air receiving tank.

2. A cleaner for dust laden air, comprising a ilrst air lmet passageway, a second vertically disposed air passageway, for upward travel o! the air, communicatingat its lower part with the .lower part of the iirst passageway, a. third vertically disposed passageway in the form of a venturi, for downward travel of the air, the top portions of said second and third passageways being in communication, impingement surfaces in the lower part of the third passageway for pulverizing liquid impinging thereagainst, means for spraying liquid in each of the three passageways, a fourth passageway having its lower portion in communication with the lower portion of the third passageway, a spray eliminator and a clean air outlet in said fourth passageway, and means, at the bottom of the apparatus, for collecting slurry from the several passageways.

ERNEST F. FISHER. 

